1. Technical Field
The present invention relates to a medium feeding apparatus which feeds a medium from a roll body around which the medium is wound.
2. Related Art
An ink jet printer which is an example of a medium feeding apparatus will be described as an example. Among these ink jet printers, an ink jet printer is known, which is provided with a spindle motor applying torque for rotating a roll body to the roll body and a torque control device controlling the spindle motor. The torque control device measures a current value being output to the spindle motor for rotating the spindle motor by operating the spindle motor. Also, based on a measured result of the current value, a setting torque of the spindle motor is set (refer to JP-A-2009-208921).
In the medium feeding apparatus, there is a case in which load being applied to a roll driving portion, characteristics of the roll driving portion, or the like, at the time of rotating the roll body is changed in a stop period of the roll driving portion, and as a result, output values to the roll driving portion for rotating the roll body are changed. In this case, even in a case where, after the stop period of the roll driving portion, the roll driving portion is controlled using the output measured values which are measurement result of the output values to the roll driving portion for rotating the roll body, and are measured before the stop period of the roll driving portion, the roll driving portion cannot be appropriately operated. In addition, after the roll driving portion is stopped, measuring again of the output value to the roll driving portion takes time and efforts.